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Why no BC (back course) approaches in Europe?

It is a LOC-only approach.

With a normal CDI, the deviation bar reads backwards. With an HSI/EHSI it reads correctly so it is a normal LOC approach.

I wonder why Europe has not gone for them. They would enhance safety at the many airports which have an ILS on just one runway end and nothing in the other.

Administrator
Shoreham EGKA, United Kingdom

With an HSI/EHSI it reads correctly so it is a normal LOC approach.

In theory yes but not if you set HSI inside DC LOC zone and cross “confusion cone” to fly on BC LOC signal, you will have to rest HSI of flip-flop frequency to pick BC LOC on HSI again…

Last Edited by Ibra at 02 Jan 09:41
Paris/Essex, France/UK, United Kingdom

Even with an HSI it’s all too easy to mess up and forget to set it follow the BC. With just a CDI, I think it would take tremendous concentration to get it right. Fine as an exercise but not something I’d want to do in IMC and serious terrain. Kind of like flying with reversed ailerons – theoretically possible but not many people out there who’ve done it and survived (though I do know one).

There ARE BC approaches in the US but I’m pretty sure I’ve never flown one, except maybe when I was an IR student. There’s also the famous LOC BC on the missed for Aspen.

LFMD, France

I think you always need to go missed on VOR/NDB or Radar or RNAV (especially if you are at full scale deflection on ILS), the DC/BC LOC is only used for initial approach guidance or final missed guidance, I would be interested if there is LOC IAP flown on DC/BC for final approach & initial missed? it’s too good to be true…

Of course one can dead recon their way out in IMC on feelings before picking BC/DC LOC signal again (like in SRA & PAR where one has to find MAPT and go missed on crystal ball in IMC or watch & compass for the unlucky one all the way between RTR max range point where ATC let-down guidance stops untill the point where ATC radar is back to life again)

Pretty sure LOC signal on ILS Cat1 (no Cat3 behind) are unusable for turn guidance 1nm past LLZ emitter (or 2nm past MAPT or under M/DH), there is no guarantee to even pick it again if one is lost off course without flying sensible heading (maybe it’s usable while spirling up above circling height and trying to fetch it 2nm past LLZ antenna?), in any case the RNAV on tablet HSI would offer a better safety record for going missed than BC LOC?

PS: Chambery initial missed is done on NDB, the BC LOC is used for guidance after passing overhead NDB…

Last Edited by Ibra at 02 Jan 11:50
Paris/Essex, France/UK, United Kingdom

I would be interested if there is LOC IAP flown on DC/BC for final approach & initial missed? it’s too good to be true…

https://aeronav.faa.gov/d-tpp/2113/00252LBC27L.PDF

Melbourne, Florida (KMLB)

LFMD, France

Peter wrote:

The deviation bar (on an EHSI at least) works the same way as before.

Yes, on a (E)HSI, but not on a traditional CDI. And even on a (E)HSI the deviation bar works the same way only if you enter the reciprocal of the track you’re actually going to fly. (My first guess would be that the accident pilot forgot that.) And of course you must remember to select BC on the FD/AP and not APR/NAV.

Last Edited by Airborne_Again at 02 Jan 13:50
ESKC (Uppsala/Sundbro), Sweden

Thanks, it confirms what I had in mind: the minima on BC LOC are exactly those of circling and missed is done on VOR/DME not on DC LOC

No different than flying ILS end then circle to land with the bonus of using BC LOC to intercept the non-ILS end if visual perspective is tough…

Last Edited by Ibra at 02 Jan 14:23
Paris/Essex, France/UK, United Kingdom

Before widespread addition of RNAV (GPS) straight in approaches to almost all runways, Localizer Back Courses were common in the US, but now they are being phased out. Currently in the entire US, only 61 back course approaches remain and it is very difficult to find one to practice with. They are going the way of other unused conventional approach types, such as VOR/DME RNAV – 0, LDA – 1, SDF -1, LDA -31. Even the legacy GPS stand alone approaches designed before the RNAV TERPS specification (RNP APCH) are slowly being retired, currently only 78 remain. These are out of a total of 6949 RNAV approaches and 5029 conventional approaches currently in the US.

KUZA, United States

Peter writes:

I wonder why Europe has not gone for them. They would enhance safety at the many airports which have an ILS on just one runway end and nothing in the other.

The only one I have known in Northern Europe is (was?) Kiel-Holtenau
EDHK on 08/26 using the same frequency 109.5 joined by a Teardrop from the same LOC in the direction you required. [Replaced, I suspect, now by the RNP’s: Although, unusually, they too require a Teardrop join and not the usual ‘T’ approach.]
The last time I flew a BC was aeons ago when I took my FAA IR Checkride.

Last Edited by Peter_G at 03 Jan 08:11
Rochester, UK, United Kingdom

I am afraid you don’t remember correctly. Kiel never had a BC approach. In fact, Germany never had any.

In Germany it is not too uncommon to have the same LOC frequency for two opposing runway ends, but they are both proper ILS approaches.

Mainz (EDFZ) & Egelsbach (EDFE), Germany
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